NASA’s James Webb Telescope has completed cryogenic vacuum testing at the Johnson Space Center in Houston. The historic telescope spent a total of 90 days in Chamber A at Johnson before the 40-foot, 40-ton chamber door was unsealed on November 18.
“After 15 years of planning, chamber refurbishment, hundreds of hours of risk-reduction testing, the dedication of more than 100 individuals through more than 90 days of testing, and surviving Hurricane Harvey, the OTIS cryogenic test has been an outstanding success,” said the project manager for the James Webb Space Telescope at NASA’s Goddard Space Flight Center, Bill Ochs. “The completion of the test is one of the most significant steps in the march to launching Webb.”
The James Webb telescope was sealed in Chamber A on July 20. The chamber was then cooled down to cryogenic temperatures over 30 days using “liquid nitrogen and cold gaseous helium shrouds”. It then spent the next 30 days being vigorously tested to ensure that every component operated as expected when subjected to the extreme cold of space. The last 30 days of the cryogenic vacuum test gradually raised the temperature to ambient conditions by pumping air back into the chamber.
Through its 90 days of testing, the James Webb satellite performed within specifications. Jonathan Homan, project manager for Webb’s cryogenic testing at Johnson praised both the telescope and the testing team for this huge milestone in the telescope’s development. “With an integrated team from all corners of the country, we were able to create deep space in our chamber and confirm that Webb can perform flawlessly as it observes the coldest corners of the universe.”
In addition to surviving the cold of Chamber A, the James Webb telescope also had a close shave with hurricane Harvey. The hurricane passed over the Johnson Space Center causing minor damage to the center’s launch facilities. Scientists and engineers at Johnson overseeing Webb’s cryogenic vacuum testing braved the storm performing overnight shifts as the category 4 hurricane ranged outside.
The James Webb Telescope is set to launch aboard an Ariane 5 rocket by mid-2019.
Image Credit: NASA/Chris Gunn
